Air-heating furnace with liquid heat transfer means



J. E. SCHARFF Filed Feb. 4, 1949 il!! Iffflll/ l INVENTOR BYJohn E.Schorff ZM f f. w( ATTORNEY Oct. 30, 1951 AIR-HEATING EURNACE WITHLIQUID HEAT TRANSFER MEANS FIGA- Patented Oct. 30, 1 951 AIR-HEATINGFURNACE WITH LIQUID HEAT TRANSFER MEANS John E. Scharff, New Rochelle,N. Y.

Application February 4, 1949, Serial No. 74,670

2 Claims.

My invention is an improved heating apparatus, particularly a heater oflarge capacity in comparison with its size; and adapted to circulatewarmed air for indoor spaces, such as oices, apartments and dwellings.

An important object of my invention is to provide a heater of unitaryconstruction and design, simple and relatively inexpensive to produceand assemble, having a high operating efficiency, and easy to inspectand repair.

Another object is to provide a heater wherein the heating medium, suchas air, is warmed in successive stages; thus utilizing to the greatestdegree the fuel consumed in the process.

The nature' and advantages of the invention are fully described herein,and the drawings illustrate one or more practical embodiments oi theheater. But this disclosure is explanatory only, and variations instructural details can be adopted without deviation from the generalplan that characterizes the improvement.

On the drawings;

Figure l is a vertical sectional view through a heating apparatusaccording to this invention.

Figure 2 is a section through a part of the apparatus, showing amodification seen from one side.

Figure 3 is a View of the same parts seen from one end; and

Figures 4, 5 and`6 show details of the heater.

top of the housing, though of course they may l be placed elsewhere. Thehousing has an interior partition 4, dividing the unit into twocompartments 5 and 6; the air entering the former; and, after beingheated to the required degree, being discharged from the latter. Withinthe outlet chamber 6 is the casing 'l of a heater unit containing watertubes or pipes 8, arranged in zigzagging tiers between the Vbottom andthe top of the casing l. The other chamber 5 contains a blower fan orimpeller 9, which effects the transfer of the air from the one chamberto the other; this fan causing a ow of air from the inlet chamber 5 tothe chamber 5 through a suitable opening in the partition 4. In thecasing I is a combustion chamber I@ at the lower end, the lower portionof the walls of the casing 'I having a suitable fire-resistant lining. Aburner is shown at II, with a nozzle I2 for liquid or gaseous fuelentering the space I0. I, of course, can use any heating unit that isthe equivalent of that disclosed herein.

Each tier of ,tubes 8 includes several tubes disposed side by side, thetubes of one tier being staggered with respect to the tubes in the tiersimmediately above and below it. The casing I is closed at the sides,bottom and top, and the products of combustion are passed through asmoke flue I3 connected to the casing 'I at the top and passing throughthe partition 4 and across the housing I and out of the latter. Thisflue spans the chamber 5 just below the inlet 2. Between this flue andthe inlet 2 is a heating member or radiator I4, consisting of a numberof pipes connected to the uppermost tubes 8. To this radiator is coupledan outlet pipe I5 leading to a hot water heater I'I; and beyond thisheater I'I is a pipe leading to pump I8, and then to a pipe or conduit I9 coupled to the lowermost tubes 8.

The fan 9 and the pump I8 are both driven by an electric motor 2U, whichis connected to the fan and pump respectively by belts ZI and 22.

In operation, the fuel, such as oil or gas consumed in the space I0,heats the water in the tubes 8, and the burnt gases flow out through theilue I3. Hot water from the uppermost tubes 8 ows through the radiatorI4. The incoming air comes into contact with the radiator I4 and itstemperature is raised as a result. Reaching the flue I3, which acts asanother heating member, the air now has its temperature furtherincreased; and the warmed air next enters the fan casing and is forcedthrough an opening in the partition 4 into the compartment 6. Here itabsorbs more heat from the walls of the casing l; and has its maximumtemperature when the air passes out through the opening 3. This outletmay be connected to air flues to lead the air to points where heating isneeded, or the heater may deliver the air directly into the spacecontaining the housing I. The air is thus heated in several stages as itflows through the heater, and the operation is very ecent. The maximumeffect is obtained from the fuel burnt in the chamber I0. The fan ofcourse delivers through the lowest part of the partition.

Within the casing l, and ailixed to opposite walls thereof arehorizontal supports in the form of brackets or angle irons 24 forheaders 23 connected to both ends of the tubes 8 of each tier thereof.From the header coupled to the pipe I9, the lower most tubes cross at anincline to the lowest header on the opposite wall ofthe casing;

being connected to this header adjacent the bottom. Other tubes of thisheader are connected thereto near the top and lead across the casing atan upward incline to the lower part of the next header, just above thefirst. As indicated on Figure 4, the tubes of one tier are staggeredwith respect to the tubes above and below; so that some of the tiershave one more tube than the rest. Thus the hot gases of combustion whichflow upward in the casing 7, make contact with an aggregate heatingsurface of the maximum extent, and the water in thetubes 8 is quicklyheated to the required degree. The pipe 25 connects the header of theuppermost tubes 3 to the member I4.

The radiator is is connected to an expansion tank 26, and has a ventcock 21 at the top. In the tank I1 is a coil IE, that is supplied withwater through an inlet pipe 28; and the contents of this coil i6 aredischarged as hot water for domestic use from an outlet pipe 32 coupledto the coil I6 at the top. To the pipe I9 is joined a feed pipe 29having a relief feed and relief valve. A three Way cock 30 is used tocut off the pipe 28V so that the coil l5 can be back-flushed and cleanedof sediment. The pipe 29 has a drain cock 3|. Preferably an air filter33 is in the inlet opening 2.

In Figures 1 and 4 the heater sections made up of the tubes 8 and theheaders 23 are of steel, and are joined by Welding. On Figures 2 and 3,the heater members have the form of cast iron sections 34, and eachincludes headers 35 joined by water pipes 35. The sections are joined bycoupling or push nipples 3l in such a way that the water in the sectionsflows in zigzag fashion as before through them from bottom to top. Thewidth and depth of the casing 'i are as indicated in Figures 2 and 4,the -depth being somewhat greater than the width. All of the sections 34have the same length as shown in Figure 2, but some may be narrower, asindicated on Figure 3. The top and bottom sections 34 may have seventubes each, for example, the middle `section six; and the sectionsadjacent top and bottom sections may also have six tubes each. Betweenthe last named sections and the central section, the two remainingsections have five tubes each, such a section being indicated on Figure6. The tubes of the successive sections are staggered as before, withrespect Vto the tubes above and below them. This construction is just aseflicient and advantageous as the first design above described. Theheaders are spaced from the casing l, and the heating medium therein,passing into the radiator I4, acts only on the air entering thecompartment 5 to raise its temperature. The burner i2 also heats thewalls of the casing 1, and the air impelled by the blower into thecompartment 6 is forced into contact with the casing 'l and itstemperature is increased again. This construction is very efficient.With one actual installation for example, the incoming air had atemperature of 60 degrees F. at the inlet, and this was raised to 127degrees by the radiator I4. At the outlet 3 the air after contact withthe. casing 1, had a temperature of over 160 degrees. When the blower 9is not operating the casing l acts to prevent loss of heat from thepipes 8 and headers 23.

The radiator I4 also comprises headers joined by pipes in two layers,and these pipes may carry outside iins 38.

Other appliances than oil or gas burners for heating may be employed.

Having described my invention, what I believe to be new is:

1. Heating apparatus comprising a housing having a vertical partitiontherein dividing it into two compartments, one having an outlet at thetop and the other an inlet at the top, a casing containing heatersections including hollow headers spaced from the walls of the casingand conduits connecting said headers in the one compartment, a burnerlocated within the casing and adjacent the sections for heating thesame, a hollow heater member comprising conduits in the othercompartment adjacent the inlet thereof and conduit means connecting theheater member to said sections, a smoke flue connected to the top of thecasing and extending through the other compartment at the top thereofadjacent said heater member to the outside of the housing, the partitionhaving an opening adjacent burner end of the casing, an impeller mountedto discharge through the opening in said partition, and a return lineconnecting the heater member to said sections adjacent said burner endof said casing, a pump in said return line, and a motor in the housingconnected -to the impeller and the pump.

2. Heating apparatus comprising a housing having a partition thereindividing it into two compartments, one having an outlet and the other aninlet, a casing containing heater sections including hollow headersspaced from the walls of the casing and conduits connecting said headersin the one compartment, a burner 1ocated within the casing and adjacentthe sections for heating the same, a hollow heater member comprisingconduits in the other compartment adjacent the inlet thereof and conduitmeans connecting the heater member to said sections, a smoke flueconnected toy the casing and extending through the other compartmentthereof adjacent said heater member to the outside of the housing, thepartition having an opening adjacent the burner end of said casing, animpeller mounted to discharge through the opening in said partition, anda return line connecting the heater member to said sections adjacentsaid burner end of .said casing, a pump in said return line, and amoto-r in the housing connected to the impeller and the pump. f

JOHN E. SCHARFE.

REFERENCES CITED The following references are of record in the rile ofthis patent:

UNITED STATES PATENTS Number Name Date 208,822 Hulings Oct. 8, 18781,846,292 Whiteley Feb. 23, 1932 2,190,998 Summers Feb. 20, 19402,212,222 Aust-in Aug. 20, 1940 2,225,181 Powers Dec. 17, 1940 2,249,554Daly July 15, 1941 2,269,055 Gower Jan. 6, 1942 2,363,742 Norton Nov.28,` 1944 FOREIGN PATENTS Number Country Date 401,743 Germany Sept. 8,1924

